RANKING · 2020 CENSUS · 33 SHOWN OF 33

Largest by population, New Mexico counties · 2020

The most populous us counties as of the 2023 estimates. This list covers the 33 counties in New Mexico that qualify, ranked against each other statewide.

New MexicoAll states All rankings

SAME RANKING BYCities States Metros ZIP codes

RELATEDFastest growing Fastest shrinking Most densely populated Most sparsely populated Best broadband access Worst broadband access

YEAR1990 2000 2010 2020 2025

RANKPLACESTATEPOPTOTAL POPULATIONVS 2000

01Bernalillo County, NMNM667,601676,444+22%

02Doña Ana County, NMNM229,091219,561+26%

03Santa Fe County, NMNM156,907154,823+20%

04Sandoval County, NMNM159,565148,834+66%

05San Juan County, NMNM120,340121,661+7%

06Valencia County, NMNM82,01376,205+15%

07Lea County, NMNM74,74974,455+34%

08McKinley County, NMNM68,11972,902−3%

09Otero County, NMNM70,36867,839+9%

10Chaves County, NMNM63,36465,157+6%

11Eddy County, NMNM62,50962,314+21%

12Curry County, NMNM46,65548,430+8%

13Rio Arriba County, NMNM39,83240,363−2%

14Taos County, NMNM34,56434,489+15%

15Grant County, NMNM27,25228,185−9%

16San Miguel County, NMNM26,26027,201−10%

17Cibola County, NMNM26,80727,172+6%

18Luna County, NMNM25,40725,427+2%

19Lincoln County, NMNM19,84420,269+4%

20Los Alamos County, NMNM19,40719,419+6%

21Roosevelt County, NMNM18,61519,191+7%

22Socorro County, NMNM15,83816,595−8%

23Torrance County, NMNM16,10015,045−11%

24Colfax County, NMNM12,18412,387−13%

25Sierra County, NMNM11,39511,576−13%

26Quay County, NMNM8,4548,746−14%

27Guadalupe County, NMNM4,3434,452−5%

28Mora County, NMNM4,0514,189−19%

29Hidalgo County, NMNM3,9294,178−30%

30Union County, NMNM3,8444,079−2%

31Catron County, NMNM3,8273,579+1%

32De Baca County, NMNM1,6471,698−24%

33Harding County, NMNM617657−19%

SHOWING 1–33 OF 33

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UPDATED 2026-06-02 · DATA: US CENSUS BUREAU ACS 5-YEAR ESTIMATES